A témába vág, csupán érdekességként:
"A major drop in temperature 137 million years ago briefly interrupted the warm, equable climate of the Cretaceous Period. The water temperature in the Arctic Ocean fell from around 13°C to between 4 and 7°C, possibly causing the poles to freeze over."

"Current findings indicate that the global climate during the Cretaceous Period was warm and equable with high atmospheric CO2 values, although scientists have already speculated that this global warmth may have been punctuated by colder episodes."
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